The sequence of cellular dysfunctions in preclinical Alzheimer's disease must be understood if we are to plot new therapeutic routes. Hippocampal neuronal hyperactivity is one of the earliest events occurring during the preclinical stages of Alzheimer's disease in both humans and mouse models. The most common hypothesis describes amyloid-β accumulation as the triggering factor of the disease but the effects of this accumulation and the cascade of events leading to cognitive decline remain unclear.
View Article and Find Full Text PDFPowering and communicating with sensors placed behind metal walls is required in various applications such as submarine hulls, pressurized tanks or pipes. Acoustic power transfer (APT) is an excellent option to supply these sensors without making through holes. However, the power transfer performances of APT systems can be strongly degraded by the destructive interferences of emitted waves, typically when the receiver diameter is smaller than the transmitter's one.
View Article and Find Full Text PDFThe low-power sensing platform proposed by the Convergence project is foreseen as a wireless, low-power and multifunctional wearable system empowered by energy-efficient technologies. This will allow meeting the strict demands of life-style and healthcare applications in terms of autonomy for quasi-continuous collection of data for early-detection strategies. The system is compatible with different kinds of sensors, able to monitor not only health indicators of individual person (physical activity, core body temperature and biomarkers) but also the environment with chemical composition of the ambient air (NO, CO, NH particles) returning meaningful information on his/her exposure to dangerous (safety) or pollutant agents.
View Article and Find Full Text PDFPurpose: Reducing the risk of exacerbation is a long-term goal of managing moderate-to-severe asthma. The use of fluticasone propionate/formoterol fumarate dihydrate (FP/FORM) pressurized metered-dose (pMDI, Flutiform), a type of inhaled corticosteroid (ICS) and long-acting β2 agonist (LABA) fixed-dose combination, has been associated with lower oral corticosteroid-requiring exacerbation rates than other ICS/LABA fixed-dose combinations, fluticasone propionate/salmeterol xinafoate (FP/SAL) and budesonide/formoterol fumarate (BUD/FORM). This study presents the first budget impact analysis of drug and exacerbation management cost savings associated with the increased access to FP/FORM compared to the currently available ICS/LABAs for treating moderate-to-severe asthma in Singapore.
View Article and Find Full Text PDFAlterations of excitatory synaptic function are the strongest correlate to the pathologic disturbance of cognitive ability observed in the early stages of Alzheimer's disease (AD). This pathologic feature is driven by amyloid-β oligomers (Aβos) and propagates from neuron to neuron. Here, we investigated the mechanism by which Aβos affect the function of synapses and how these alterations propagate to surrounding healthy neurons.
View Article and Find Full Text PDFGlaucoma is the leading cause of blindness in the developed and developing world. Not only is the clinical impact of this disease considerable, but associated economic and humanistic burdens - affecting patients, caregivers, and society - are substantial. Since glaucoma is an age-related disorder and populations in many developing countries are aging at a faster pace than in the developed world, increasing attention is being focused on ways to ameliorate the burdens of illness.
View Article and Find Full Text PDFClinicoecon Outcomes Res
November 2018
Cancer pain is one of the most common, feared, debilitating, and often undertreated symptoms among cancer patients. It needs attention since it has a significant impact on the quality of life (QoL) of the patients. Also, since cancer has emerged as a major health problem in developing countries, there is a need to strengthen preventive strategies for effective cancer pain management and provide comfort to cancer patients.
View Article and Find Full Text PDFAmyloid-β (Aβ) drives the synaptic impairment and dendritic spine loss characteristic of Alzheimer's disease (AD), but how Aβ affects the actin cytoskeleton remains unknown and contentious. The actin-binding protein, cofilin-1 (cof1), is a major regulator of actin dynamics in dendritic spines, and is subject to phospho-regulation by multiple pathways, including the Rho-associated protein kinase (ROCK) pathway. While cof1 is implicated as a driver of the synaptotoxicity characteristic of the early phases of AD pathophysiology, questions remain about the molecular mechanisms involved.
View Article and Find Full Text PDFBackground: Excessive synaptic loss is thought to be one of the earliest events in Alzheimer's disease (AD). However, the key mechanisms that maintain plasticity of synapses during adulthood or initiate synapse dysfunction in AD remain unknown. Recent studies suggest that astrocytes contribute to functional changes observed during synaptic plasticity and play a major role in synaptic dysfunction but astrocytes behavior and involvement in early phases of AD remained largely undefined.
View Article and Find Full Text PDFThe substantia nigra pars reticulata (SNr) is a major output nucleus of the basal ganglia circuitry particularly sensitive to pathological dopamine depletion. Indeed, hyperactivity of SNr neurons is known to be responsible for some motor disorders characteristic of Parkinson's disease. The neuronal processing of basal ganglia dysfunction is well understood but, paradoxically, the role of astrocytes in the regulation of SNr activity has rarely been considered.
View Article and Find Full Text PDFBackground: The substantia nigra pars reticulata (SNr) is a major output nucleus of the basal ganglia, delivering inhibitory efferents to the relay nuclei of the thalamus. Pathological hyperactivity of SNr neurons is known to be responsible for some motor disorders e.g.
View Article and Find Full Text PDFFluorescent staining of astrocytes without damaging or interfering with normal brain functions is essential for intravital microscopy studies. Current methods involved either transgenic mice or local intracerebral injection of sulforhodamine 101. Transgenic rat models rarely exist, and in mice, a backcross with GFAP transgenic mice may be difficult.
View Article and Find Full Text PDFThe present study was initiated to gain some information about the tissue distribution of transient receptor potential proteins of C-type (TRPC), a family of voltage-independent cation channels, at the beginning of neurogenesis in the telencephalon of embryonic mice. The mRNAs of all known TRPCs (TRPC1-TRPC7) could be found in the cortex at E13. TRPC1, TRPC3 and TRPC5 were the main isoforms, whereas the mRNAs for TRPC2, TRPC4, TRPC6 and TRPC7 were less abundant.
View Article and Find Full Text PDFMaurocalcine (MCa) is a 33-amino acid residue peptide that was initially identified in the Tunisian scorpion Scorpio maurus palmatus. This peptide triggers interest for three main reasons. First, it helps unravelling the mechanistic basis of Ca(2+) mobilization from the sarcoplasmic reticulum because of its sequence homology with a calcium channel domain involved in excitation-contraction coupling.
View Article and Find Full Text PDFIn spermatozoa, voltage-dependent calcium channels (VDCC) have been involved in different cellular functions like acrosome reaction (AR) and sperm motility. Multiple types of VDCC are present and their relative contribution is still a matter of debate. Based mostly on pharmacological studies, low-voltage-activated calcium channels (LVA-CC), responsible of the inward current in spermatocytes, were described as essential for AR in sperm.
View Article and Find Full Text PDFSpontaneous calcium activity can be detected in embryonic mouse cortical slices as fluorescence intensity variations, in the presence of a fluorescent calcium indicator. Current methods to detect and quantify these variations depend heavily on experimenters whose judgement may interfere with measurement. In the present work, we developed new software called CalSignal for automatic detection and tracking of cellular bodies and quantification of spontaneous calcium activity on time-series of confocal fluorescence images.
View Article and Find Full Text PDFIn the embryonic brain, post-mitotic cortical neurons migrate from their place of origin to their final location. Various external factors such as hormones, neurotransmitters or peptides regulate their migration. To date, however, only a few studies have investigated the effects of these external factors on the electrical properties of the newly formed embryonic cortical neurons.
View Article and Find Full Text PDFMaurocalcine (MCa) is a 33-amino acid residue peptide toxin initially isolated from the scorpion Scorpio maurus maurus. Its structural and functional features make it resembling many Cell Penetrating Peptides. In particular, MCa exhibits a characteristic positively charged face that may interact with membrane lipids.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 2005
Before synaptogenesis, early excitability implicating voltage-dependent and transmitter-activated channels is known to be crucial for neuronal development. We previously showed that preplate (PP) neurons of the mouse neocortex express functional Na(+) channels as early as embryonic day 12. In this study, we investigated the role of these Na(+) channels in signaling during early development.
View Article and Find Full Text PDFStore-operated channels (SOCs) are recruited in response to the release of Ca2+ from intracellular stores. They allow a voltage-independent entry of Ca2+ into the cytoplasm also termed capacitative Ca2+ entry (CCE). In neurons, the functional significance of this Ca2+ route remains elusive.
View Article and Find Full Text PDFBiochem Biophys Res Commun
July 2001
Contrary to bacterial DNA, mammalian DNA contains very little if any N(6)-methyldeoxyadenosine (MDA). The possible biological effect of this nucleoside on eukaryotic cells has been studied on different tumor cell lines. Addition of MDA to C6.
View Article and Find Full Text PDFGene transfer into muscle by electroporation with low-voltage and long-pulse (LV/LP, 100 V/50 msec) currents was shown to be more efficient than simple intramuscular DNA injection. Nevertheless, transgene expression declined from day 7 and only reached 10% of the maximum 3 weeks after electroporation. We have optimized electroporation conditions including voltage, pulse number, and the amount of injected luciferase-encoding plasmid DNA in the tibialis anterior muscle.
View Article and Find Full Text PDFContradictory experimental results and human trials have questioned the clinical relevance of the HSVtk/ganciclovir system. To bypass the problem of transfection efficiency, we used a glioma cell line stably expressing the HSVtk gene, which was also fully characterized from gene to protein. We also designed a more clinically relevant experimental protocol, consisting of late GCV delivery on large tumor formations.
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